Just as the Celtics seemingly solidified the center position prior to the 2010-11 season, the same could be said for two-guards. They featured a Hall of Fame starter (Ray Allen[3]) along with a tough combo guard (Delonte West[4]), a lengthy swingman (Marquis Daniels[5]) and a shoot-first scorer (Von Wafer[6]). The latter three are unrestricted free agents this offseason, and there’s a chance any of the trio could return.

As we’ve noted before, the Celtics have six players under contract in 2011-12 for a combined $64.3 million (Kevin Garnett[7], $21.2; Paul Pierce[8], $15.33; Ray Allen, $10; Rajon Rondo[9], $10; Jermaine O’Neal, $6.23; Avery Bradley[10], $1.53), and Jeff Green[11] is due at least another $5.91 million this offseason.

However, unlike the center situation, there will be a ton of quality available shooting guards. As a result, Celtics president Danny Ainge can more easily upgrade the team as a whole by dedicating what little money he’ll have available to a two-guard once the free agency frenzy opens on Dec. 9.

Without further ado, let’s take a look at the options that should be available to the Celtics at shooting guard, separating the current free-agent players into four categories.

THE VON WAFERS

Is it possible that Von Wafer is the homeless man’s Von Wafer? The Celtics ranked 23rd in points per game this past season, and they desperately need scorers who can provide instant offense off the bench. Obviously, Wafer himself is a last resort, but these guys would obviously provide an upgrade.

Why? Generally not interested in defense or ball-handling, Richardson can score in a variety of ways — knocking down 3-pointers (150-plus in last two seasons) and posting up smaller guards (he’s 6-foot-6).

Why not? Considering he’s only 30 years old (seems older, right?) and made $14.4 million from the Suns and Magic this past season, Richardson should command more dollars than the Celtics can dish out.

Why? The NBA’s Sixth Man of the Year in 2010, Crawford is capable of scoring 30-plus points off the bench on any given night — creating on his own, catching-and-shooting or getting to the line.

Why not? Whether or not the Celtics will be able to afford Crawford’s services depends on how big of a pay cut from $10.1 million he’d be willing to take. And, if you’re being picky, he’s a shaky defender whose shooting percentages regressed this past season.

Why? Were you as surprised as I was that Young averaged 21.9 points per 40 minutes, albeit on an awful Wizards team? His 40-inch standing vertical leap and shooting touch translate into buckets.

Why not? Where do we begin? For someone athletic enough to jump out of a barrel with his hands tied behind his back, Young doesn’t defend (effort?) or rebound (awful rate: 4.9%). He also sees the floor like Stevie Wonder, recording the worst assist rate for regular shooting guards the last two seasons.

Why? Dunleavy found his shooting stroke again, making 40 percent of his 3-point attempts for the second time in his 10-year career, and his 6-foot-9 frame translates into a handful of rebounds a night.

Why not? While he can create for others, Dunleavy might not beat Larry Flynt off the dribble — or stay in front of him defensively (although he’s savvy enough as a team defender). Dunleavy has played at least 60 games the last two seasons, but he hasn’t been the same since a devastating 2009 right knee injury.

Why? One of the game’s great shooters when healthy, Redd averaged 20-plus points for six straight seasons from 2003-08. Plus, he has a long-standing relationship with former Bucks teammate Ray Allen.

Why not? Redd suffered a series of knee injuries that kept him from 185 games over the final three years of a six-year, $90.9 million deal in Milwaukee, but he might be worth a flyer on a veteran minimum contract.

THE DELONTE WESTS

Obviously, there can only be one Delonte West (as evidenced by his NSFW freestyle rap about KFC[17]), and he may be the best available option as a guy who can spell Rajon Rondo or play alongside him in addition to providing defensive toughness at both guard positions. If the Celtics aren’t willing to or capable of ponying up enough money to retain the injury-prone West, these guys are worth a look.

Why? The cash-strapped Kings have more guards in their backcourt than Lindsay Lohan has drug charges, so a team could steal the 24-year-old Sixth Man in the making by raising the price on his $1.1 million qualifying offer. After being traded from the Hornets to Sacramento, Thornton produced better numbers across the board than Jamal Crawford — not to mention the fact he’s a better defender.

Why not? Thornton takes care of the ball, but he doesn’t pass too much. He can get to the basket almost at will, but he’s not too speedy. And he’s not a particularly great shooter, but he might shoot too much.

Why? Brown is athletic enough to make up for some of his ‘tweener height (6-foot-4) to provide a turbo boost to the fast break, some highlight dunks[20] and quality defense (when he feels like it).

Why not? For starters, Brown once tweeted[21]: ‘Ok let me put a end to this right now before it goes any further. I DID NOT SLEEP WITH @paugasol woman!!! First and last time addressing it!’ To say he’s a questionable teammate is an understatement. He also has trouble handling the ball and shooting the 3.

THE MARQUIS DANIELSES

While Daniels hasn’t ruled out a return to Boston[22], his health is a big question mark after undergoing spinal surgery in March. These alternatives are also long and athletic, capable of guarding either wing position defensively and scoring double digits off the bench offensively.

Why? Stevenson doesn’t lack testicular fortitude. During the Mavericks’ run to the title, he played an invaluable role offensively (56.5 percent from 3 in the NBA Finals[24]) and defensively (on Dwyane Wade[25]).

Why not? Persistent back problems have led to a combined 36.3 field-goal percentage over the last four seasons for Stevenson. Not good. A loose cannon, Stevenson was arrested for public intoxication two days after winning the championship, but, hey, couldn’t all the Bruins have been cited for the same thing?

Why? Celtics coach Doc Rivers[27], who coached McGrady for four seasons in Orlando, raved about his former player prior to one meeting with the Pistons this past season. After playing fewer than 40 games in his three previous years, he played 72 and produced solid numbers in 2010-11 for the veteran minimum.

Why not? Well on his way to a Hall of Fame career, McGrady endured a series of career-threatening injuries before staying relatively healthy this past season. Sure, he’s never contributed to a team that’s survived the first round of the playoffs, but if he’s signed as a role player that shouldn’t be an issue.

Why? There were more reports about the Celtics acquiring the heady Parker — a serviceable 3-point shooter, passer and defender — via buyout than there are rumors about Tom Cruise‘s sexuality.

Why not? There wasn’t much excitement about the C’s acquiring Parker at the deadline, and there shouldn’t be now. He averaged just 8.3 points and shot less than 40 percent as a starting two-guard.

THE SASHA PAVLOVICS

Either not worth the asking price or not worth any price, like Pavlovic, these guys are a dime a dozen and wouldn’t be much of an upgrade over anybody at the league minimum (NOTE: Belinelli might be the exception, but he’s due at least $3.4 million in 2011-12). Thanks, but no thanks.

Right now, E’Twaun Moore is your backup shooting guard, so needlessly to say the Celtics will have to sign at least one and probably two of the players listed above. (Unless, as noted previously, the C’s can sign and trade Big Baby, or discover an undrafted free-agent gem out of college or overseas.)

Personally, I’d love to see Delonte West and Marquis Daniels back in Celtics uniforms but not if another team starts raising the price any higher than the veteran minimum — considering their injury issues severely impacted the C’s ability to maintain first place in the Eastern Conference this past season.

So, what to do? If I were Ainge, I’d try to lure either Jason Richardson, Jamal Crawford or Marcus Thornton (probably in that order) with the mid-level exception. And then I’d offer Tracy McGrady or Michael Redd the veteran minimum (seriously). In my eyes, that combo would be a massive upgrade.